add Lucena's pic

_data/speakers.yml

@@ -202,7 +202,7 @@
   company: Griffith University
   title: 
   bio: Lucena Miranda is a secondary school teacher from the Philippines who completed her master’s degree at the University of Queensland. She is now a post-confirmation PhD student at Griffith University, researching inclusion approaches to overcome multiple disadvantages in high school. As a non-native English speaker and a mother, her skills in using various technological tools and collaborating in diverse environments have enabled her to co-publish articles and manage book publication projects, at the early stage of her PhD journey, both inside and outside academia.
-  thumbnailUrl: 
+  thumbnailUrl: lucena_miranda.png
   rockstar: false
   ribbon:
     - {abbr: "", title: "", url: ""}